Splitting water breakthrough

18 May 2011

An international team of scientists led by Monash University has found the key to the hydrogen economy could come from a very simple mineral, commonly seen as a black stain on rocks.

Their findings, developed with the assistance of researchers at UC Davis in the USA and using the facilities at the Australian Synchrotron, was published in the journal Nature Chemistry on 15 May 2011.

Professor Leone Spiccia from the School of Chemistry at Monash University said the ultimate goal of researchers in this area is to create a cheap, efficient way to split water, powered by sunlight, which would open up production of hydrogen as a clean fuel, and leading to long-term solutions for our renewable energy crisis.

To achieve this, they have been studying complex catalysts designed to mimic the catalysts plants use to split water with sunlight. But the new study shows that there might be much simpler alternatives.

"Birnessite, it turns out, is what does the work. Like other elements in the middle of the Periodic Table, manganese can exist in a number of what chemists call oxidation states. These correspond to the number of oxygen atoms with which a metal atom could be combined," Professor Spiccia said.

Co-author on the research paper was Dr Rosalie Hocking, Research Fellow in the Australian Centre for Electromaterials Science who explained that what was interesting was the operation of the catalyst, which follows closely natures biogeochemical cycling of manganese in the oceans.

"This may provide important insights into the evolution of Nature’s water splitting catalyst found in all plants which uses manganese centres,” Dr Hocking said.

The work was primarily funded by the U.S. National Science Foundation and the U.S. Department of Energy Monash University, the Australian Research Council through the Australian Centre of Excellence for Electromaterials Science, and the Australian Synchrotron.